Does anyone know how to create the first administrator userID?

[2ma2]

I "inherited" an OnDemand instance on zOS, for which there seems no userID with administrator restrictions.
If I look in the ARSUSER Table I find among other users the userID: ADMIN.
I once resat the password for the ADMIN userID on a Windows OD, but when I do this on this in the ARSUSER table on zOS I do not get prompted for new a password.

So how do I move on?

[2ma2]

Never mind

set the SRVR_FLAGS_SECURITY_EXIT=0 to avoid RACF check og userID
And hereafter able to change ADMIN password.